How Does the Fruit Fly Population Evolve So Quickly?

Generations

• Fruit flies are tiny gnatlike insects with red eyes and tan bodies. These pests are able to evolve quickly due to their short life cycle, and the fact that they produce a higher number of generations compared to other species. Fruit flies start as larvae, grow into adults then die within 10 days of hatching. In this short time, the fruit fly breeds, producing generation after generation. Evolution and adaptations occur between generations. Thus, the short and rapid life cycle of the fruit fly, coupled with the hurried reproduction of new generations, allows this bug to evolve almost before your very eyes.

Environments

• Fruit fly populations evolve quickly to adapt to their environment. When introduced to a new environment, the fruit fly population will adapt by 95 percent within the decade, giving them the ability to survive in new habitats. Fruit fly populations that are separated by geography are no longer compatible with members of their own family due to rapid adaptations. Evolution changes these species in order to for them to survive in their environment and successfully reproduce.

Genes

• Fruit flies actually have a special gene that allows them to evolve faster than other species. Within the fruit fly genome, this special gene gives the fruit fly the ability to split and evolve into a new species. This gene acts as a gatekeeper, preventing viruses and bad genes from passing through and reaching the cell's nucleus. In order to be an effective gatekeeper, this gene has to evolve and adapt constantly. This gives the fruit fly the ability to evolve from the original species very quickly.

Viruses

• On occasion, a virus will make it past the gatekeeper gene, making the fruit fly a host for the virus's DNA. Viruses that make it past these gatekeeper genes do so because they have adapted; therefore, the fruit fly must continually adapt to ward off viruses. This adaptation causes the fruit fly to evolve at a rapid pace.

Gene Replication

• Fruit flies also have genes that continually replicate. Replicating genes adapt to be able to make it past gatekeeper genes. For this reason, the gatekeepers must adapt to keep replicating genes under control. Without this balance, the replicating genes would take over. The adaptation that takes place to keep fruit fly genes under control causes them to evolve faster than other species.